Process and apparatus for continuously relaxing textile yarns

ABSTRACT

A textile yarn is continuously relaxed during its advance through a relax tube extending along the path of advance of the yarn and an accumulation tube wherein the yarn is accumulated so as to stay therein for a predetermined time by flowing a heating medium through the relax tube and the accumulation tube.

United States Patent 1 1 [111 3,729,831 Kosaka et a1. May I, 1973 PROCESS AND APPARATUS FOR [5 1] Int. Cl ..F26b 3/10 CONTINUOUSLY RELAXING TEXTILE [58] Field of Search ..34/ 156, 157, 160, YARNS 34/13, 10, 23; 28/1.4, 72 HR [75] Inventors: Kenzo Kosaka, Chigusa-ku, Nagoyashi, Aichi-ken; Kiyoshi Adachi, [56] References f"' F UNITED STATES PATENTS ken; Himshi Kltagawa, Monyamaku, Nagoya-shi Aichi-ken; Tu- 2,586,800 2/1952 Elvin et a1 ..34/57 R nehika Nakamura, Ni hLk 3,482,294 12/1969 Joly Nagoywshiy Aichiqwm ()sami Kata, 3,644,968 2/1972 Elliott et a1 ..28/l.4 Moriyama-ku, Nagoya-shi, Aichiken, all of Japan Primary ExaminerWi11iam F. ODea [73] Assignee: Mitsubishi Rayon Company Limited, Assistant Exammer Larry L Schwartz Attorney-James E. Armstrong et a1. Tokyo, Japan [22] Filed: Dec. 7, 1971 [57] ABSTRACT PP N0: 77 A textile yarn is continuously relaxed during its ad- Vance through a relax tube extending along the path of [30] Foreign Application Priority Data advance of the yarn and an accumulation tulae wherein the yarn is accumulated so as to stay therein Dec. 7, 1970 Japan 45/107935 for a predetermined time by fl i a heating medium through the relax tube and the accumulation tube. [52] US. Cl. ..34/23, 28/1.4, 28/72 HR,

17 Claims, 8 Drawing Figures Patented May 1, 1972.

5 Sheets-Sheet 1 Patentd May 1, 1973 5 Sheets-Sheet Patented May 1, 1973 5 Sheets-Sheet 3 Patented May 1, 1973 3,729,831

.5 Sheets-Sheet 4 jjl/l/ Patented May 1, 1973 3,729,831

5 Sheets-Sheet 5 PROCESS AND APPARATUS FOR CONTKNUOUSLY RELAXING TEXTILE YARNS The present invention relates to a method and apparatus for continuously relaxing textile yarns such as natural and synthetic multifilament yarn and spun yarn and synthetic split fiber yarn.

Generally speaking, synthetic fiber bulky yarns are conventionally prepared through the following processes.

1. A synthetic filament tow is drawn at a high temperature. A portion of the drawn filament tow is draftcut so as to form a sliver of staple fibers and thereafter, the sliver is heat-treated under tensionless conditions so as to relax it. The other portion of the drawn filament tow is cut into staple fibers and the staple fibers are formed into a sliver. The relaxed fiber sliver and the non-relaxed fiber sliver are blended in a predetermined proportion, and then the blend sliver is spun into a yarn. The spun yarn is heat-treated with a heating medium such as steam under tensionless conditions, whereby the spun yarn is converted into a high bulk yarn.

2. A filament yarn consisting of synthetic conjugate filaments each of which is composed of two polymer constituents adhering side by side along the length of the filament and having shrinking properties different from each other, is heat-treated under tensionless conditions so as to convert it to a bulky yarn in which the conjugate filaments are spontaneously crimped due to the differential shrinkage between the two constituents.

In the conventional processes as mentioned above, the heat-treatment for developing the bulkiness is applied to a hank of the filament yarn or spun yarn, and thereafter, the hank is subjected to a treatment such as scouring, bleaching and dyeing. That is, the heat-treatment is discontinuously carried out in a batch system. Such a discontinuous process has the defects that to form the yarn into a hank is very complicated and it is necessary to rewind the yarn from the hank.

Further, when a large number of yarn hanks are divided into a plurality of groups and heat-treated in a plurality of batches, it is very difficult to prevent variation of shrinkage of the yarn from batch to batch. This variation results in non-uniform qualities of the resultant bulky yarn and unevenness of dyeing.

If it is possible to continuously carry out the relaxing process while advancing the original yarn, the abovementioned disadvantages will be completely eliminated and hence, it will be possible to produce a high bulk yarn having uniform qualities at very low cost with high efficiency.

An object of the present invention is to provide a process and apparatus for continuously relaxing textile yarns capable of eliminating the above-stated disadvantages of the conventional prior arts.

Another object of the present invention is to provide a process for continuously and easily relaxing textile yarns in combination with a winding step of the yarn.

A further object of the present invention is to provide an apparatus for continuously relaxing textile yarns which can be compactly arranged in combination with a winding device for the yarn.

By the process and apparatus of the present invention, the relax step and the wind up step for the yarn which are separately carried out in the prior arts, can be successively and continuously carried out so as to significantly shorten the processing time, and hence, to obtain a bulk yarn having uniform qualities.

in the process of the present invention, a textile yarn is sucked into a relax tube by action of a heating medium jetted into the relax tube along the path of advance of the yarn, the sucked yarn is advanced by the current of the jetted heating medium through the relax tube while being prerelaxed, the prerelaxed yarn is accumulated in an accumulation tube under a tensionless condition, the yarn accumulation is carried through the accumulation tube by flowing a heating medium through the yarn accumulation, further relaxing the yarn. When the relaxed yarn is delivered from the accumulation tube, a cooling medium is blown towards the upper end portion of the accumulation tube along the delivery path of the yarn in a direction opposite to that of advance of the yarn so as to cool the relaxed yarn while unravelling entanglements and intertwining of the yarn within the accumulation and preventing the accumulated yarn from overrun from the accumulation tube. The heating and cooling mediums are forcibly exhaust through an exhaust duct.

The process of the present invention can be effected by the apparatus of the present invention which comprises, in combination, a feed nozzle device for sucking the textile yarn by jetting a heating medium, a relax tube through which the yarn is carried by the flow of the heating medium while prerelaxing the yarn, an accumulation tube in which the yarn is accumulated so as to be further relaxed under tensionless conditions and through which the yarn accumulation is conveyed the current of the heating medium, a box for covering the accumulation tube, a delivery nozzle device for delivering the relaxed yarn while cooling it with a cooling medium, and means for forcibly exhausting the heating and cooling mediums.

The feed nozzle device includes a path for feeding the yarn into the relax tube therethrough and a nozzle for jetting the heating medium into the relax tube. The nozzle opens at the entry of the relax tube and surrounds the yarn feed path so that the heating medium jet formed through the nozzle slit sucks the yarn into the relax tube through the yarn feed path. The relax tube extends from the feed nozzle device to the accumulation tube.

The accumulation tube has a plurality of openings on the periphery thereof and an open end.

The outside box surrounds the accumulation tube and has a closed end around the relax tube and an open end around the open end of the accumulation tube.

The delivery nozzle device includes a path for delivering the relaxed yarn therethrough and a nozzle for blowing the cooling medium therethrough. The nozzle opens facing the open end of the accumulation tube and surrounds the yarn delivery path so as to cool the yarn being delivered from the accumulation tube with the cooling medium blown through the nozzle slit.

The exhaust means for the heating and cooling medium is connected to the outside box, the open end of the accumulation tube and the cooling medium nozzle slit.

The features and advantages of the present invention will be illustrated in detail with reference to the accompanying drawings in which:

FIG. 1 is a perspective view showing an arrangement containing three sets of the apparatus of the present invention,

FIGS. 2 to 4 are all cross-sectional front views showing embodiments of the apparatus of the present invention, and

FIGS. to 8 are all perspective views of embodiments of accumulation tubes in the apparatus of the present invention.

FIG. 1 shows an arrangement containing three sets of apparatus for continuously relaxing and then winding up a textile yarn such as a spun yarn, multifilament yarn or split yarn.

Referring to FIG. 1, a yarn A is supplied from a supply package 1 to a relaxing device 30 by means of a pair of feed rollers 2a and 2b at a predetermined rate. As shown in FIGS. 2 to 4, the relaxing device 30 comprises a feed nozzle device 3 facing the feed rollers 20 and 2b, a relax tube 6 connected to the nozzle device 3, an outside box 7 covering an accumulation tube 19 which is shown in FIGS. 2 to 4 but not in FIG. 1, connected to the relax tube 6, and a delivery nozzle device connected to the outside box 7.

A heating medium is fed into the feed nozzle device 3 through a main duct 4 and a branched conduit 5 and then jetted into the relax tube 6 through the nozzle device. The yarn A having passed through the feed rollers 2a and 2b is sucked by action of the heating medium jet into the relax tube 6 through the feed nozzle device 3. The yarn A thus sucked is upwardly advanced with the heating medium stream through the relax tube 6 and prerelaxed by the heat of the heating medium.

Next, the yarn A is accumulated in the accumulation tube 19 in the outside box '7 under a tensionless condition for a predetermined period so as to be completely relaxed by the heat of the heating medium. The accumulated yarn A is carried upwardly through the accumulation tube 19 by the current of the heating medium stream, and then delivered from the open top end of the accumulation tube 19 through the delivery nozzle device 10 by means of delivery rollers 12a and 12b. A cooling medium is blown toward the open top end of the accumulation tube 19 through the delivery nozzle device 10 in order to cool the relaxed yarn A. The cooling medium thus blown is discharged into the atmosphere together with the heating medium which has passed through the accumulation of the yarn A in the accumulation tube 19 through a branched exhaust conduit 8 and the main exhaust duct 9.

The yarn A advances through guide rollers 11a and 1 1b and delivery rollers 12a and 12b and then is wound up into a take-up package 14 by means of a driving drum 13.

As is clear from FIG. 1, the elements of the apparatus of the present invention are combined into a compact assembly hence, the apparatus can be arranged at a position below the conventional winder such as a split drum winder or spindle drive winder, so as to provide ease of handling.

FIG. 2 shows a preferred embodiment of the apparatus of the present invention.

Referring to FIG. 2, the feed nozzle device 3 comprises an outside tube 3a, an intermediate tube 312 and an inside tube 15b. The inside tube 15b has therein an entrance path 15a for sucking the yarn A and a coneshaped nozzle 16 which converges upwardly is formed between the outside surface of the inside tube 15b and the inside surface of the intermediate tube 3b. The outside tube 30 has an annular groove 17b surrounding the periphery of the intermediate tube 3b.

The cone-shaped nozzle 16 is connected to the annular groove 17b through numerous apertures formed on the intermediate tube 3b, and the annular groove 17b is connected to a conduit 5 which is connected to a heating medium source (not shown in the drawing).

The cone-shaped nozzle 16 has an opening of crosssectional area smaller than that of the conduit 5. Accordingly, when the heating medium is supplied into the cone-shaped nozzle 16 through the conduit 5, the heating medium is jetted into the relax tube 6 through the cone-shaped nozzle 16 at a velocity higher than that through the conduit 5. The yarn A is sucked into the relax tube 6 through the entrance path 15a, and upwardly carried through the relax tube 6 by the forward flow of the heating medium. During its advance through the relax tube 6, the yarn A is heated by the heating medium so as to prerelax the internal stress existing in the yarn A and preshrink it. The relax tube 6 may have a heater l8 surrounding the periphery thereof as shown in FIG. 2. The heater 18 may be selected from electric heater or heater jacket and heater coil through which a heating medium is recycled, or the like. During the advance of the yarn A, it is importance that the yarn A does not touch the inside surface of the relax tube 6. If the yarn A touches the inside surface, the yarn A may fuse and adhere to the inside surface, or numerous flys produced from the yarn A due to the contact melt-fix on the inside surface. Such adherence of the yarn A or melt-fixing of flys causes the heating medium to flow unevenly through the relax tube 6, and this uneven flow of the heating medium further aggravates the undesired adhering and melt-fixing. Accordingly any contact of the yarn A with the inside surface of the relax tube 6 must be avoided. In order to achieve this, it is necessary that the heating medium jetted through the cone-shaped nozzle 16 produces no eddy current within the relax tube 6. Therefore, it is important that the feed nozzle device 3 has no constructional characteristic which may create such a heating medium eddy current.

The top end of the relax tube 6 is connected to the lower end 19a of the accumulation tube 19 having numerous apertures 20 on the periphery thereof. As stated above, the yarn A is conveyed by the heating medium stream upwardly into the accumulation tube 19 and accumulated there, so as to stay therein for a predetermined period under a tensionless condition. During its stay in the accumulation tube 19 the yarn A is completely relaxed and shrunk by the heat of the heating medium. After passing through the accumulation of the yarn A, the heating medium is flowed into the outside box 7 through the apertures 20. During this time, the accumulation of the yarn A partly blocks the apertures so as to intercept the flow of the heating medium through the apertures. Accordingly, the intercepted heating medium stream forces the accumulation of the yarn A so as to convey it upwardly through the accumulation tube 19.

The delivery nozzle device) comprises an inside tube 310 for defining therein an exit path 31b for the yarn A and an outside tube 32a surrounding the inside tube 31a. A cone-shaped nozzle 32b converging downwardly is formed between the outside surface of the inside tube 31a and the inside surface of the outside tube 32a. The cone-shaped nozzle 32a is connected to a cooling medium source (not shown in the drawing) through a conduit 211.

After completely relaxing and shrinking, the yarn A is delivered from the open end 1% of the accumulation tube 19 through the exit path 31b. The cooling medium is fed from the source thereof into the cone-shaped nozzle 32b through the conduit 21 and blown through the cone-shaped slit 32b toward the open end 1% of the accumulation tube 19. That is, the cooling medium is blown along the delivery path of the yarn A in a direction opposite to that of advance of the yarn A so as to cool the yarn A. Such blowing of the cooling medium has the following advantages.

1. Since the cooling medium is blown in a direction opposite to the direction of advance of the yarn A, the yarn A is exposed always to the flesh cooling medium during its advance between the accumulation tube 19 and the exit path 31b. Therefore, the yarn A can be cooled at high efficiency.

2. Since the cooling medium is blown along the delivery path of the yarn A in a direction opposite to the advance of the yarn A, the entanglements or intertwinings of the accumulated yarn A formed during accumulation are unravelled by this action of the cooling medium. This is effective for preventing the exit path 31b from closure by muss of the entangled or intertwined yarn A.

3. Since the cooling medium is blown onto the accumulation of the yarn A in the accumulation tube 19 under considerable pressure, the yarn accumulation which is conveyed upwardly by the heating medium stream, is protected from overrun from the accumulation tube 19.

The cooling medium thus blown flows into an exhaust duct 9 through a conduit 8 connected to the outside box 7 together with the heating medium which has passed into the outside box 7 through the apertures 20, and then, the mixture of the cooling and heating mediums is forcibly exhausted into the atmosphere by means of a suction device (not shown in the drawing). A damper 22 is disposed in the conduit 8 for the purpose of adjusting the flow rate of the exhaust.

FIG. 3 shows another preferred embodiment of the apparatus of the present invention. In the drawing, a supplementary exhaust opening 23a is formed on the periphery ofthe outside box 7. A portion of the heating medium from the apertures of the accumulation tube 19 flows into a supplementary exhaust duct through a supplementary exhaust conduit 23b and is then naturally passed into the atmosphere without any exhausting device. A supplementary damper 24 is disposed in the conduit 23b in order to control the flow rate of the heating medium. It is necessary that supplementary exhaust of the heating medium is not forcible carried out. If the supplementary exhaustion is forcibly effected by means of, for example, an exhaust fan, a portion of the accumulation of the yarn A in the accumulation tube 19 is forced into the apertures 20 by the heating medium suction. This causes not only the disadvantage that the apertures 20 are excessively blocked by the yarn A but the disadvantage that the portion of the yarn A is drawn into the apertures 20 so as to obstruct the upward advance of the accumulation of the yarn A.

Further, forced suction will result in the disadvantage that an excess of the cooling medium is sucked into the supplementary duct 25 through the accumulation of the yarn A in the accumulation tube 19 so as to excessively cool the accumulation, impede the upward advance of the accumulation, and to condense the heating medium in the outside box 7.

Compared with the construction as shown in FIG. 2, the construction as shown in FIG. 3 has the advantages detailed below.

In the case where saturated or super heated steam is used as the heating medium in the apparatus of FIG. 2, sometimes, the exhaust steam from the accumulation tube 19 condenses in the outside box 7 before the exhaust steam reaches the exhaust conduit 8 so as to produce water condensation. Particularly, the exhaust steam flowing through the apertures 20 distributed on the lower periphery of the accumulation tube 19 frequently condenses in the outside box 7.

The further the apertures 20 are from the exhaust conduit 8 through which the heating medium is exhausted, the lower the suction effect of the apertures 20. Therefore, the heating medium is sucked through the apertures 20 located on the lower periphery of the accumulation tube 19 at a flow rate lower than that through the apertures 20 located on the upper periphery. As stated above, since the suction of the heating medium in the lower portion of the accumulation tube 19 is effected in a non smooth manner, there is a tendency for the bottom level of the accumulation of the yarn A to vary with variation of the flow rate of the heating medium flowing through the lower portion of the accumulation tube 19.

However, in the apparatus as shown in FIG. 3, the heating medium flowed through the apertures 20' on the lower periphery of the accumulation tube 19 can be smoothly exhausted into atmosphere through the supplementary exhaust conduit 23b and the supplementary exhaust duct 25. Accordingly, the abovestated disadvantages of the apparatus of FIG. 2 are not found in the apparatus of FIG. 3.

The apparatus as shown in FIG. 4 is suitable for continuously relaxing and shrinking the yarn A at a high velocity. When the yarn A has a high shrinking property, sometimes, the yarn A can not be completely shrunk by the heating medium supplied through the feed nozzle device 3. In this case, it is effective for completely shrinking the yarn A that, as shown in FIG. 4, the outside box 7 is laterally partitioned into an upper chamber 7a and a lower chamber 7b with a partition 27, and a supplementary heating medium supply conduit 26 is connected to the lower chamber 78. The heating medium at a predetermined temperature is fed into the lower chamber 7b through the supplementary supply conduit 26 and then flows into the lower portion of the accumulation tube 19 through the apertures 20 thereof. The yarn A accumulated in the accumulation tube 19 is heated by the heating mediums fed through the feed nozzle device 3 and the relax tube 6 and the additional heating medium fed through the lower chamber 7b and the apertures 20 so as to completely relax and shrink the yarn. The heating medium in the accumulation tube 19 flows into the upper chamber 7a through the apertures 20 in the upper portion of the accumulation tube periphery. In the case where the apparatus of FIG. 4 is utilized, the heating medium flowing through the accumulating tube 19 has a flow rate and pressure higher than those of FIGS. 2 and 3. Since the higher flow rate and pressure, sometimes, causes overrun of the yarn A from the accumulation tube 19, it is desirable that the cooling medium flows at a rate and pressure higher than those of FIGS. 2 and 3.

Referring to FIG. 4, the supplementary supply conduit 26 and the box 7 are covered by a heater 28 in order to elevate the temperature of the heating medium flowing therethrough, and to enhance the relaxing effect on the yarn A.

In the art of the present invention, the accumulation tube 19 is an important element for effectively accomplishing the objects of the present invention. Accordingly, it is necessary that the accumulation tube has the following capabilities.

1. The yarn accumulation being received in the accumulation tube is carried upwardly successively without undesirable entanglement and intertwining of the yarn.

2. A sufficient capacity and provided with numerous apertures.

The apertures must be formed with the total opening area balanced against the amount of the yarn to be accumulated in the accumulation tube. The term opening area ratio percentage used hereinafter means the ratio in percent of the total opening area of the apertures to the total area of the accumulation tube periphery.

3. The size and shape of the apertures are related to the thickness of the yarn and fineness of the filaments.

FIGS. 5 to 8 all show various accumulation tubes usable in the apparatus of the present invention. However, the accumulation tube usable for the art of the present invention is not in any way limited to the embodiments as shown in FIGS. 5 to 8.

Referring to FIG. 5, the accumulation tube 19 is a cylinder provided with numerous apertures 20. For example, the accumulation tube 19 has an inside volume of 24,210 mm and an opening area ratio percentage of the apertures of 14.4 percent, and the aperture has a circular shape and a diameter of 1.6 mm. An accumulation tube having these dimensions is suitable for processing a yarn of 6 18 meter count while accumulating 8 to 9 meter of the yarn therein.

Referring to FIG. 6, the accumulation tube 19 converges downwardly and has the advantage that in the tube, the yarn is accumulated in a stable condition with less entanglements and intertwinings of the yarn than those in the accumulation tube shown in FIG. 5 and the yarn accumulation is prevented from reversal. For example, the accumulation tube of FIG. 6 has an inside volume of 19,310 mm, an opening area ratio percent age of apertures of l 1.3 percent, and the aperture has a circular shape and a diameter of 1.0 mm. An accumulation tube having the above-mentioned dimensions is suitable for processing yarn of 12 to 36 meter count at an accumulation of the yarn of7 to 8 meter.

Referring to FIG. 7, the accumulation tube 19 is composed of an upwardly converging upper cone and a downwardly converging lower cone connected to each filament yarn which has a tendency to entangle and to reverse its yarn accumulation or a low count spun yarn which has a tendency to form numerous fibrils on its surface.

The accumulation tube of FIG. 7, for example, has an inside volume of 9,692 mm an opening area ratio percentage of apertures of 9.1 percent, and is provided with circular apertures of 0.6 mm diameter. An accumulation tube having these dimensions is useful for processing a spun yarn of 24 to 64 meter count and a conjugate yarn of to 500 denier.

Referring to FIG. 8, the accumulation tube 19 downwardly converges and has a plurality of slits 20a extending along the length of the tube 19. The accumulation tube 19, for example, has an inside volume of 32,620 mm and an opening area ratio percentage of 8.2 percent, and the slits have a width of 2.0 mm. Such an accumulation tube is useful for relaxing a conjugate yarn and a spun yarn having a relatively high thickness.

The following examples are intended to illustrate the application of the present invention but are not intended to limit the scope thereof in any way.

EXAMPLE I A spun yarn of s 2/36 consisting of acrylonitrile polymer fibers and having a shrinkage in boiling water of 24.5 percent was continuously relaxed and shrunk into a high bulk yarn by utilizing the apparatus as shown in FIGS. 1 and 3.

In the apparatus, the accumulation tube had a configuration as shown in FIG. 6 and an inside volume of 19,310 mm and was provided with numerous circular apertures of 1.0 mm diameter with an opening area ratio percentage of 11.3 percent. The relax tube was covered by an electric heater of W.

The spun yarn was fed into the relax tube through the feed path of the feed nozzle device at a velocity of 420 m/min.

In order to heat the fed spun yarn, saturated steam at a pressure of 1.1 kglcm 'G was jetted into the relax tube through the nozzle of the feed nozzle device at a feed rate of 1.1 kg/hr and heated to a temperature of 128 C in the relax tube. The spun yarn was advanced through the relax tube and then accumulated in the accumulation tube over a length of 9 m for 1.7 seconds so as to sufficiently relax and shrink it. The shrunk yarn was cooled by air at room temperature at a pressure of 0.5 kgfcm 'G and blown through the nozzle slit of the delivery nozzle device. The cooled yarn was delivered at a velocity of 327 m/min through the delivery path of the delivery nozzle device. That is, the spun yarn was fed at an overfeed ratio of 22 percent. The term overfeed ratio" used herein refers to a ratio of the difference between the feed velocity and the delivery velocity to the feed velocity. The resultant yarn had a shrinkage in boiling water of 1.8 percent and an excellent bulkiness.

EXAMPLE 2 The procedure of Example 1 was repeated for a spun yarn of l/56" consisting of acrylonitrile polymer fibers and having a shrinkage in boiling water of 25 percent utilizing the apparatus as shown in FIGS. 1 and 3.

In the apparatus used, the accumulation tube had a configuration as shown in FIG. 7 and an inside volume of 9,692 mm and was provided with numerous circular apertures of 0.6 mm diameter with an opening area ratio percentage of 9.1 percent, and the relax tube was covered by an electric heater of l 10 W.

The processing for the spun yarn was carried out under the conditions detailed below.

temperature having a pressure of 0.3

kg/cm 'G The resultant yarn had a shrinkage in boiling water of 1.8 percent and an excellent bulkiness.

EXAMPLE 3 The procedure of Example 1 was repeated for relaxing and shrinking a polypropylene conjugate filament yarn of 180 denier/60 filaments having a shrinkage in boiling water of 25 percent utilizing the apparatus shown in FIGS. 1 and 3. The shrinkage in boiling water mentioned above was determined from the yarn in hank form.

In this apparatus, the accumulation tube had a configuration as shown in FIG. 7 and an inside volume of 9,692 mm and provided with numerous circular apertures of 0.6 mm diameter with an opening area ratio percentage of 9.1 percent. The relax tube was covered by an electric heater of l W.

The processing of the polypropylene filament yarn was effected under the conditions detailed below.

. Heating medium: saturated steam of 1.0 kglcm fl pressure 2. Feed rate of heating medium: 0.95 kg/hr 3. Temperature of steam in relax tube: 126C 4. Feed velocity of yarn: 820 m/min 5. Delivery velocity of yarn: 492 m/min 6. Overfeed ratio: 40percent 7. Length of accumulated yarn: 24 m 8. Accumulating time: 2.9 sec.

9. Cooling medium: air at room temperature having a pressure of 0.35 kg/cm .G

The resultant yarn had a shrinkage in boiling water of 3.3 percent and a crimp contraction of 23 percent. The crimp contraction was determined as follows.

A crimped yarn is stretched to a length 1 under a load of 100 mg/d for 1 minute and to a length 1 under a load of 1 mg/d for 1 minute, therefore the crimp contraction of the yarn can be expressed by the following equation:

Crimp contraction in percent =I -l /l, X 100 EXAMPLE4 The procedure of Example 1 was repeated for a spun yarn of 2/36" consisting of acrylonitrile polymer fiber and having a shrinkage in boiling water of 29 percent by employing the apparatus as shown in FIGS. 1 and 2. The apparatus was provided with an accumulation tube having a configuration as shown in FIG. 5 and an inside volume of 24,210 mm and provided with numerous circular apertures of 1.6 mm diameter with an opening area ratio percentage of 14.4 percent. The relax tube was covered by an electric heater of 130 W.

The processing of the spun yarn was carried out under the conditions as detailed below.

. Heating medium: saturated steam having a pressure 2. Feed rate of heating medium: 1.4 kg/hr 3. Temperature of steam in relax tube: 132C 4. Feed velocity of yarn: 420 m/min 5. Delivery velocity of yarn: 327 m/min 6. Overfeed ratio: 22%

7. Length of accumulated yarn: 10 m 8. Accumulating time: 1.8 sec.

9. Cooling medium: air at room temperature having a pressure of 0.6 kg/cmfi The resultant yarn had a shrinkage in boiling water of 2.8 percent and an excellent bulkiness.

EXAMPLE 5 The procedure of Example 4 was repeated for the same spun yarn as used in Example 4 and utilizing the apparatus shown in FIGS. 1 and 4. The accumulation tube and relax tubewere the same as those of Example 4 and the supplementary supply conduit for the heating medium was covered by an electric heater of W.

The processing of the spun yarn was performed under the condition as detailed below.

1. Heating medium supplied to feed nozzle and supplementary feed circuit: saturated steam having a pressure of 1.2 kg/cm .G

2. Feed rate of heating medium in the nozzle it. 1.4 kg/hr Overfeed ratio: 22% Feed rate of heating medium in supplementary supply conduit: 8. Length of accumulated yarn:

9. Accumulating time:

10. Cooling medium:

3. Temperature of steam in relax tube: 132C 4. Feed velocity of yarn: 680 m/min 5. Delivery velocity of yarn: 531 m/min 6.

2.4 kg/hr.sp. 7 m

0.8 sec.

air at room temperature having a pressure of 0.9 kg/cm .G

EXAMPLE 6 A spun yarn of 3/65" consisting of acrylonitrile polymer fibers and having a shrinkage in boiling water of 26 percent was relaxed and shrunk into a high bulk yarn suitable for example, for hand knitting by using the apparatus shown in FIGS. 1 and 3.

The apparatus includes an accumulation tube having a configuration as shown in FIG. 6 and a relatively large inside volume of 144,100 mm and is provided with numerous circle apertures each of 2.2 mm diameter with an opening area ratio percentage of 12.3 percent, and a relax tube covered by an electric heater of W.

The spun yarn was processed under the following conditions.

having a pressure of 1.3 kg/cmfi 2. Feed rate of heating medium: 1.4 kg/hr 9. Cooling medium: air at room temperature having a pressure of 0.8

The relaxed yarn had a shrinkage in boiling water of 1 1.7 percent and an excellent bulkiness.

What we claim is:

l. A process of continuously relaxing a textile yarn comprising; v

a. prerelaxing a textile yarn by sucking it into a relax tube by jetting a heating medium along the direction of advance of said yarn and advancing it through said relax tube with the jet of said heating medium,

. further relaxing said prerelaxed yarn by accumulating it in 'an accumulating tube under a tensionless condition, flowing said heating medium through said yarn accumulation and carrying said yarn accumulation through said accumulation tube,

c. delivering said relaxed yam from the open end of said accumulation tube,

(1. blowing a cooling medium toward the open end portion of said accumulation tube along the delivery path of said yarn in a direction opposite to the direction of advance of said yarn in order to cool said relaxed yarn while unravelling entanglements and intertwinings of said accumulated yarn and preventing said accumulated yarn from overrun from said accumulation tube, and

e. forcibly exhausting said heating medium which has passed through said yarn accumulation and said cooling medium which has passed through said yarn delivery path, through an exhaust duct.

2. A process as set forth in claim 1, wherein a portion of said heating medium having passed through said yarn accumulation is forcibly exhausted and the remaining portion of said heating medium is naturally exhausted through a supplementary exhaust duct.

3. A process as set forth in claim 1, wherein an additional heating medium is flowed into said yarn accumulation through a lower side portion of said yarn accumulation.

4. A process as set forth in claim 1, wherein said relax tube is heated to prevent condensation of said heating medium flowing therethrough.

5. A process as set forth in claim 1, wherein said heating medium flowing around said accumulation tube is heated to prevent it from condensation.

6. A process as set forth in claim 1, wherein said heating medium is selected from hot air, saturated steam or superheated steam.

7. A process as set forth in claim 1, wherein said cooling medium is cold air.

8. An apparatus for continuously relaxing a textile yarn comprising;

a. a feed nozzle device provided with means for defining a yarn feed path and means for defining a nozzle slit surrounding said yarn feed path through which nozzle a heating medium is jetted,

b. a relax tube extending from said feed nozzle device, c. an accumulation tube extending from-said relax tube and having a plurality of openings on the periphery thereof and one end open, an outside box covering said accumulation tube,

e. a delivery nozzle device provided with means for defining a yarn delivery path and means for defining a nozzle slit for forming and blowing a cooling medium around said yarn delivery path and opening in face of said open end of said accumulation tube, and

f. means for forcibly exhausting said heating medium and said cooling medium, said means is connected to said outside box, said cooling medium nozzle slit, and said accumulation tube open end.

9. An apparatus as set forth in claim 8, further comprising means for naturally exhausting a portion of said heating medium, said means connected to said outside box.

10. An apparatus as set forth in claim 8, wherein said outside box is laterally partitioned into an upper chamber and a lower chamber, and said lower chamber is connected to a heating medium supply conduit.

11. An apparatus as set forth in claim 8, wherein said relax tube is surrounded by a heater.

12. An apparatus as set forth in claim 10, wherein said outside box is surrounded by a heater.

13. An apparatus as set forth in claim 8, wherein said accumulation tube is a cylindrical tube.

14. An apparatus as set forth in claim 8, wherein said accumulation tube is a downwardly converging coneshaped tube.

15. An apparatus as set forth in claim 8, wherein said accumulation tube is composed of an upwardly converging cone-shaped upper tube and a downwardly converging cone-shaped lower tube connected to each other.-

16. An apparatus as set forth in claim 8, wherein said opening on said accumulation tube periphery is a circular opening.

17. An apparatus as set forth in claim 8, wherein said opening on said accumulation tube periphery is a slit extending along the length of said accumulation tube. 

1. A process of continuously relaxing a textile yarn comprising; a. prerelaxing a textile yarn by sucking it into a relax tube by jetting a heating medium along the direction of advance of said yarn and advancing it through said relax tube with the jet of said heating medium, b. further relaxing said prerelaxed yarn by accumulating it in an accumulating tube under a tensionless condition, flowing said heating medium through said yarn accumulation and carrying said yarn accumulation through said accumulation tube, c. delivering said relaxed yarn from the open end of said accumulation tube, d. blowing a cooling medium toward the open end portion of said accumulation tube along the delivery path of said yarn in a direction opposite to the direction of advance of said yarn in order to cool said relaxed yarn while unravelling entanglements and intertwinings of said accumulated yarn and preventing said accumulated yarn from overrun from said accumulation tube, and e. forcibly exhausting said heating medium which has passed through said yarn accumulation and said cooling medium which has passed through said yarn delivery path, through an exhaust duct.
 2. A process as set forth in claim 1, wherein a portion of said heating medium having passed through said yarn accumulation is forcibly exhausted and the remaining portion of said heating medium is naturally exhausted through a supplementary exhaust duct.
 3. A process as set forth in claim 1, wherein an additional heating medium is flowed into said yarn accumulation through a lower side portion of said yarn accumulation.
 4. A process as set forth in claim 1, wherein said relax tube is heated to prevent condensation of said heating medium flowing therethrough.
 5. A process as set forth in claim 1, wherein said heating medium flowing around said accumulation tube is heated to prevent it from condensation.
 6. A process as set forth in claim 1, wherein said heating medium is selected from hot air, saturated steam or superheated steam.
 7. A process as set forth in claim 1, wherein said cooling medium is cold air.
 8. An apparatus for continuously relaxing a textile yarn comprising; a. a feed nozzle device provided with means for defining a yarn feed path and means for defining a nozzle slit surrounding said yarn feed path through which nozzle a heating medium is jetted, b. a relax tube extending from said feed nozzle device, c. an accumulation tube extending from said relax tube and having a plurality of openings on the periphery thereof and one end open, d. an outside box covering said accumulation tube, e. a delivery nozzle device provided with means for defining a yarn delivery path and means for defining a nozzle slit for forming and blowing a cooling medium around said yarn delivery path and opening in face of said open end of said accumulation tube, and f. means for forcibly exhausting said heating medium and said cooling medium, said means is connected to said outside box, said cooling medium nozzle slit, and said accumulation tube open end.
 9. An apparatus as set forth in claim 8, further comprising means for naturally exhausting a portion of said heating medium, said means connected to said outside box.
 10. An apparatus as set forth in claim 8, wherein said outside box is laterally partitioned into an upper chamber and a lower chamber, and said lower chamber is connected to a heating medium supply conduit.
 11. An apparatus as set forth in claim 8, wherein said relax tube is surrounded by a heater.
 12. An apparatus as set forth in claim 10, wherein said outside box is surrounded by a heater.
 13. An apparatus as set forth in claim 8, wherein said accumulation tube is a cylindrical tube.
 14. An apparatus as set forth in claim 8, wherein said accumulation tube is a downwardly converging cone-shaped tube.
 15. An apparatus as set forth in claim 8, wherein said accumulation tube is composed of an upwardly converging cone-shaped upper tube and a downwardly converging cone-shaped lower tube connected to each other.
 16. An apparatus as set forth in cLaim 8, wherein said opening on said accumulation tube periphery is a circular opening.
 17. An apparatus as set forth in claim 8, wherein said opening on said accumulation tube periphery is a slit extending along the length of said accumulation tube. 